feat(effects): heat-haze sinusoidal al fons del títol (configurable a ui.yaml)

source/core/ui/ui_config.hpp

@@ -82,12 +82,20 @@ class UiConfig {
     [[nodiscard]] auto pauseExitMs() const -> int { return pause_exit_ms_; }
 
     // Escena TITLE (placeholder visual fins que tinguem artwork).
+    struct TitleHeatHaze {
+        bool enabled;
+        float amplitude_px;
+        float wavelength_px;
+        float speed_hz;
+    };
+
     [[nodiscard]] auto titleDurationMs() const -> int { return title_duration_ms_; }
     [[nodiscard]] auto titleBgColor() const -> Uint8 { return title_bg_color_; }
     [[nodiscard]] auto titleTextColor() const -> Uint8 { return title_text_color_; }
     [[nodiscard]] auto titleCopyrightColor() const -> Uint8 { return title_copyright_color_; }
     [[nodiscard]] auto titleBlinkVisibleMs() const -> int { return title_blink_visible_ms_; }
     [[nodiscard]] auto titleBlinkHiddenMs() const -> int { return title_blink_hidden_ms_; }
+    [[nodiscard]] auto titleHeatHaze() const -> const TitleHeatHaze& { return title_heat_haze_; }
 
     // Corbes d'easing triades al YAML. Si el nom no és conegut, s'usa
     // Easing::linear com a fallback.
@@ -159,6 +167,7 @@ class UiConfig {
     Uint8 title_copyright_color_;
     int title_blink_visible_ms_;
     int title_blink_hidden_ms_;
+    TitleHeatHaze title_heat_haze_;
 
     std::string menu_select_sound_;
     std::string menu_accept_sound_;